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The data collected by the DAMA/LIBRA-phase2 set-up during two additional annual cycles have been analyzed, further investigating the long-standing model-independent annual modulation effect pointed out by DAMA deep underground at the Gran Sasso National Laboratory of the I.N.F.N. by using various different experimental configurations. Including the new results, the total exposure of DAMA/LIBRA-phase2 over 8 annual cycles is 1.53 t·yr and the evidence for a signal that meets all the requirements of the model-independent Dark Matter annual modulation signature is 11.8 σ C.L. in the energy region (1 - 6) keV. In the (2 - 6) keV energy interval, where data are also available from DAMA/NaI and DAMA/LIBRA-phase1, the achieved C.L. for the full exposure of 2.86 t·yr is 13.7 σ. No systematics or side reaction able to mimic this signature (i.e., to account for the whole measured modulation amplitude and to simultaneously satisfy all the requirements of the signature) has been found or suggested by anyone throughout some decades thus far. A preliminary result on the further lowering of the software energy threshold and perspectives are also mentioned.

Some theoretical and experimental aspects regarding the direct dark matter field are mentioned. In particular some arguments, which play a relevant role in the evaluation of model dependent interpretations of experimental results and in comparisons, are shortly addressed., Comment: Proceedings of TAUP 2011 Conference

The results obtained with the total exposure of 1.04 ton × yr collected by DAMA/LIBRA-phase1 deep underground at the Gran Sasso National Laboratory (LNGS) of the I.N.F.N. during 7 annual cycles are summarized. The DAMA/LIBRA-phase1 and the former DAMA/NaI data (cumulative exposure 1.33 ton × yr, corresponding to 14 annual cycles) give evidence at 9.3 σ C.L. for the presence of Dark Matter (DM) particles in the galactic halo, on the basis of the exploited model independent DM annual modulation signature by using highly radiopure NaI(Tl) target. The modulation amplitude of thesingle-hitevents in the (2–6) keV energy interval is0.0112±0.0012 cpd/kg/keV; the measured phase is144±7days and the measured period is0.998±0.002 yr; values are in a good well in agreement with those expected for DM particles. No systematic or side reactions able to mimic the exploited DM signature have been found or suggested by anyone over more than a decade. Some of the perspectives of the presently running DAMA/LIBRA-phase2 are outlined.

Bernabei, R. "Results from DAMA/LIBRA and perspectives" in Proceedings, 9th Patras Workshop on Axions, WIMPs and WISPs (AXION-WIMP 2013) / Oberlack, Uwe, Sissol, Pierre (eds.), 2013 ; AXION-WIMP 2013 : 9th Patras Workshop on Axions, WIMPs and WISPs , 2013-06-23 - 2013-06-28, Mainz 9th Patras Workshop on Axions, WIMPs and WISPs, AXION-WIMP 2013, Mainz, Germany, 24 Jun 2013 - 28 Jun 2013; Hamburg : Verlag Deutsches Elektronen-Synchrotron, DESY-PROC 179-183 (2013). doi:10.3204/DESY-PROC-2013-04/cerulli_riccardo, The DAMA/LIBRA experiment (about 250 kg of highly radiopure NaI(Tl)) is in operation at the Gran Sasso National Laboratory of the INFN. The main aim of the experiment is to further investigate the Dark Matter (DM) particles in the Galactic halo by exploiting the model independent DM annual modulation signature. At the time of this Workshop, the DAMA/LIBRA experiment and the former DAMA/NaI one (the first generation experiment having an exposed mass of about 100 kg) have released results corresponding to a total exposure of 1.17 ton × yr over 13 annual cycles; they have provided a model independent evidence of the presence of DM particles in the galactic halo at 8.9 $σ$ C.L.. The results of a further annual cycle, concluding the DAMA/LIBRA–phase1, have been released after this Workshop and are not included here. After the upgrade at fall 2010 when all the PMTs have been replaced with new ones having higher quantum efficiency, the feasibility to decrease the software energy threshold has been demonstrated and the setup is running in this new configuration, named DAMA/LIBRA–phase2., Published by Verlag Deutsches Elektronen-Synchrotron, Hamburg

In this conference the model-independent result on the presence of dark-matter paticles in the galactic halo obtained over seven annual cycles by the 100kg highly radiopure NaI(T1) DAMA/NaI has been presented and several corollary investigations have also been discussed. More recently the model-independent result obtaind over the first four annual cycles by the second generation 250kg highly radiopure NaI(T1) DAMA/LIBRA set-up at the Gran Sasso National Laboratory of the INFN has also been released. Both the experiments have the unique feature to effectively investigate the presence of dark-matter particles in the galactic halo by exploiting the model-independent annual modulation signature. The data collected by the two experiments over elevn annual cycles for a total exposure of 0.82ton x y have pointed out at 8.2 sigma CL a positive result; several corollary model-dependent quests for the candidate particle(s) and related astrophysical, nuclear and particle physics scenarios are under updating. The future experimental activity can give rise to many new interesting results.